In my earlier U.S. Pat. No. 575226 there is described an infusible pouch or bag and cover. The infusible bag is attached at a central part of one edge of the bag to one leaf of a cover adjacent the hinge line joining the two covers made from a single sheet of cover material. The bag, which may be a tea bag or other infusible bag, when in use is positioned on the rim of a cup with the bag hanging down the inside of the cup. The leaf to which the bag is attached passes down the outside of the cup with the bag, due to the central attachment of the cover, generally conforming to the inside curvature of the cup. The other leaf is pivoted about the hinge line up to 270 to 360 degrees to thus extend away from the cup in a cantilever fashion to balance and thus support the bag in position. Thus the other leaf has to be swung away from the closed position up to nearly 360 degrees to thus stabilize and wedge the bag on the edge of the cup.
Also in my earlier U.S. Pat. No. AU587550 and Application No. AU38665/89 there are described methods and apparatus for the manufacture of the infusible bag and cover. The bags are fed onto a strip of the cover material, the bags attached thereto, the cover is creased, and then separated into separate covers each with a bag attached thereto, and finally the cover is folded about the bag. Thus the bags have to be positioned on the cover strip, and finally the cover has to be folded so that the leaves of the cover overlie the bag in a generally parallel relationship.
The above Patents describe an infusible bag which can be used as a tea bag or as a coffee bag or other infusible product and the method and apparatus for the production thereof. However with the cover and bag so produced in which the cover is formed a from a single reel or sheet of material and which is folded about a hinge line, the free leaf of the cover has to be pivoted about the hinge line nearly up to 270 to 360 degrees. However due to the nature of the material from which the cover is produced, the free leaf has a tendency to return back to less than the above angular rotation due to the inherent memory of the material from which it is produced. This could affect the stability of the bag and cover on the rim of the cup.
The above methods, apparatus and infusible bag and cover are particularly suitable for the small bags such as tea bags. However it has been found that if a larger bag for use with an infusible substance such as coffee, that certain problems arise. Thus with larger bags or pouches where the contents of the bag or pouch is increased from 2.5 grams to 7.0 grams for coffee, and although coffee has a higher density, there is still a large increase in volume and thus the size of the bag or pouch.
Thus the present invention has resulted as a result of the need to produce a cover for such a larger bag or pouch. When the previous machines were used for the production of the larger covers, problems arose in the folding of the cover strip back on itself due to the very flexible nature of the material used for it often did not fold correctly back over the bag or pouch.
Also this larger bag had user problems as it is more difficult to hold. It has been found that if a portion of the cover is in the form of a portion to be grasped, in the form of a handle that the pouch and cover after infusion of the substance, is much easier for the user to dispose of the pouch and cover. This handle is also of great advantage for the user when produced for the smaller tea bags also.
While the larger covers will use a degree of more material for the cover, there are further problems when two cover strips are used, these being supplied from twin reels, particularly on very high speed four lane production machines.
Thus the present invention overcomes the problems associated with the production of larger bags, and while the present invention is suitable for the larger bags and covers, it is also applicable to the smaller tea bags and results in a tea bag and cover with added advantages.
Thus it is an object of this invention to provide an infusible bag and cover in which a portion is provided in the form of a handle to improve ease of use by the user, particularly for larger infusions such as coffee bags.
Also it is a further object of this invention to provide an infusible bag and cover in which the free leaf does not have to pivot about its hinge line to the extent required by the above discussed product.
It is a further object of this invention to provide an infusible bag and cover in which each leaf is provided with its own hinge line or pivot line.
It is also a further object of this invention to provide an improved method and apparatus for the production of a combined infusible bag and cover.
It is a further object of the invention to provide an infusible bag and cover in which the cover is sealed around all of its edges to thus enclose the infusible bag to thus protect the contents from deterioration due to contact with the atmosphere, the flavour and aromatic constituents of the product thus being preserved.